This invention relates to an accumulator for use in vehicle air systems, and more particularly, the invention relates to suspension structures used to form the accumulators.
Accumulators are used in vehicle applications to hold pressurized air for an air suspension and/or air brakes. The accumulator is constructed from a tank that is secured to a portion of the vehicle using straps or brackets. The tank must be accommodated or packaged in a portion of the vehicle along with numerous other vehicle components. A pump provides pressurized air to the tank for storage and later used by the air suspension and brakes. Air lines run from the accumulator to the various components requiring pressurized air. In particular, an air line is necessary from the accumulator to each air spring and each brake actuator. Because many air lines are used, which can be rather long, there may be pressure loss and time lag within the air system that negatively impacts the response time of the air suspension and brakes. Furthermore, a separate accumulator secured to the vehicle increases the weight and cost of the air system by requiring numerous components.
Components in a vehicle have been used to form air conduits that carry air from an air pump to an air system component such as an air spring. For example, a portion of a side rail frame has been partitioned to carry pressurized air from the pump to an air spring. Such conduits may be insufficient to hold pressurized air which is subsequently supplied to an air system component. Moreover, providing an air conduit in a portion of the frame presents problems with servicing the conduit. Therefore, what is needed is an accumulator that may be incorporated into a portion of the vehicle while providing a serviceable accumulator.
The present invention provides an accumulator for a vehicle air system including a vehicle frame. A wheel end is spaced from the frame for supporting the vehicle frame on a roadway. A suspension assembly includes a suspension structure. The suspension structure may be a portion of an axle, a stabilizer bar, a control arm, or other suspension components. The suspension structure is interposed between the frame and the wheel end and is movable relative to the vehicle frame in response to the wheel end receiving inputs from the roadway. A fluid chamber forms the accumulator and is defined by a portion of the suspension structure for storing pressurized air. Preferably a valve is disposed within the fluid chamber to protect the valve from the environment. For light vehicle applications where a conventional air pump may be cost prohibitive, a mechanical pump may be connected between the vehicle frame and the suspension assembly. The mechanical pump provides pressurized air to the fluid chamber in response to relative movement between the suspension assembly and the vehicle frame as the vehicle travels along the roadway.
Accordingly, the above invention provides an accumulator that may be incorporated into a portion of the vehicle while providing a serviceable accumulator.